I'm not happy with the threaded rod I have for the grounding bolt through the firewall.  Further research tells me that using a brass bolt and nuts is a better solution.  Mostly I get that from looking at the grounding block that Aircraft Spruce sells, which uses brass bolts.

So, off to Lowes tonight to pick up a long brass bolt (and nuts and washers) that I will cut down to size.

I also saw on Vansairforce.com someone mentioning that they use DE-OX on the connections to the grounding bolt to protect it from corrosion.  The documentation on that says it's used for copper (which brass of course contains) and aluminum connections, so my question is: is it equally useful to use on brass connections?